Nectarine tree named ‘Smooth Zest Two’

ABSTRACT

Disclosed is a new variety of  Prunus persica  named ‘Smooth Zest Two’. This new variety, which requires 200 to 250 chilling units of dormancy, is considered to be a nectarine tree of early season maturity, which ripens in early to mid May in the medium chill zone of Texas and produces yellow fleshed fruit that are very firm, attractively colored, and suitable for both the local and regional fresh fruit market.

BACKGROUND OF THE INVENTION Field of the Invention

This invention relates to a nectarine tree referred to as a variety of Prunus persica named ‘Smooth Zest Two’. ‘Smooth Zest Two’, which requires 200-250 chilling units of dormancy, produces a high quality, firm clingstone nectarine that matures early in the season.

SUMMARY OF THE INVENTION

‘Smooth Zest Two’ is being released for use in the low to medium chill zones where cultivars such as ‘TexFirst’ (U.S. Plant Pat. No. 26,119), ‘Flordaking’ (not patented, Andrews et al., 1979), ‘Texking’ (U.S. Plant Pat. No. 14,627), and ‘Sunraycer’ (not patented, Sherman et al. 1995) are adapted. ‘Smooth Zest Two’ bears crops of clingstone, melting flesh nectarines in early to mid May in the low to medium chill zones of Texas. This new nectarine fruits well in low chill zones that receive 200-250 chilling units.

Origin of the Variety

The present nectarine tree was the result of an ongoing Stone Fruit Breeding Program of Texas A & M University, College Station, Brazos County, Tex. To this end, both controlled crosses are made each year to produce seedling populations from which improved progenies are evaluated and selected.

‘Smooth Zest Two’ (TX2B261N) [Prunus persica (Batsch) L.] originated in the Stone Fruit Breeding Program, Department of Horticultural Sciences, Texas A&M University, located in College Station, Tex. ‘Smooth Zest Two’ was selected from a cross between two unreleased nectarine selections: TX1B38N (not patented) and TX95128N (not patented). TX1B38N, the female parent, is an open pollinated seedling from ‘Sunraycer’ (not patented, Sherman et al., 1995) and TX95128N, the male parent, is a nectarine of unknown parentage derived from the Florida nectarine germplasm. The seedlings from this cross were planted in a high density selection orchard in 2002 and the selection TX1B261N was chosen as having superior fruit size and quality in 2004.

Two-year and older trees of the selections were subsequently evaluated during the 2006 through 2010 fruit growing seasons in three locations: two medium chill sites (Floresville and College Station, Tex.) and a higher chill location (Fowler, Calif.).

Asexual Reproduction of the Variety

‘Smooth Zest Two’ was bud grafted onto virus-free Nemaguard (not patented, Brooks and Olmo, 1997) peach rootstock in June 2004 at the nursery site in Oakdale, Calif. The variety was subsequently planted at the experimental orchard in the central portion of the San Joaquin Valley, near Fowler, Fresno County, Calif. and in two sites in Texas (College Station and Floresville). Fruit from the resulting propagation has been evaluated during the period from 2006 to 2010 fruit seasons. This evaluation clearly demonstrated that the re-propagated trees were true to the characteristics of the original seedling in all observable aspects.

BRIEF DESCRIPTION OF THE DRAWINGS

This new variety of nectarine tree is illustrated by the accompanying photographs. The flowers, fruit, and shoots in the pictures were obtained from a tree that was five-years old.

FIG. 1. Fruit of ‘Smooth Zest Two’ showing apical and distal views as well as fruit dissected in the axial plane to illustrate the flesh and stone characteristics.

FIG. 2. Dried endocarps of ‘Smooth Zest Two’ showing the size, shape and texture. The ruler is demarcated in millimeters.

FIG. 3. ‘Smooth Zest Two’ nectarine showing the external and internal color of the fruit and endocarp.

FIG. 4. The showy flowers of ‘Smooth Zest Two’. The ruler is in millimeters.

BOTANICAL DESCRIPTION OF THE VARIETY

Referring more specifically to the pomological details of this new and distinct variety of nectarine tree, the following has been observed under the ecological conditions prevailing at the experimental orchards in the medium chill zones of Texas. All major color code designations are by reference to The R.H.S. Colour Chart (2001; 2005) provided by The Royal Horticultural Society of Great Britain. Colors are approximate as color depends on horticultural practices such as light level and fertilization rate, among others. The trees observed were five-years old.

Tree

-   Size: Generally average to above average as compared to other common     peach and nectarine cultivars ripening in the early season of     maturity. -   Height: 3.5 m at the end of the 2012 growing season (five-years     old). -   Width: 3 m at the end of the 2012 growing season (five-years old). -   Vigor: High. -   Density: Medium to high. -   Productivity: Productive. -   Shape: The ‘Smooth Zest Two’ exhibits a generally spreading growth     habit typical of commercial varieties of nectarine such as ‘TexKing’     (U.S. Plant Pat. No. 14,627) and ‘TexRoyal’ (not patented, Byrne and     Bacon, 1991). -   Current season growth: The current season growth for the new variety     was approximately 37 to 43 inches (0.94-0.96 m). -   Regularity of bearing: Regular, and considered hardy under typical     conditions found in the low to medium chill zones of Texas and in     the central San Joaquin Valley, Calif.

Trunk

-   Size: Approximately 3.5 inches (8.9 cm) in diameter and 12 inches     (30.5 cm) in circumference when measured at a distance of     approximately 12 inches (30.5 cm) above the soil level, at the end     of the 2012 growing season on a five-year old tree. -   Bark texture: Considered moderately rough with numerous folds of     papery scarf-like skin being present. -   Bark coloration: Variable, colors present are 189C-D of the     Greyed-Green Group, 200B-D of the Brown Group and 201C-D of the Grey     Group.

Branches

-   Size: Considered medium small to medium for the variety. -   Thickness and length: Medium small to medium (about 2.2 cm in     diameter as measured 10 cm from the trunk on a five-year old tree)     as compared to other varieties. The length of the branches are     limited by pruning to a 3 to 5 foot (approximately 0.9 to 1.5 m)     length depending on the position in the tree. -   Surface texture: Average and appearing furrowed on wood that is     several years old. -   Lenticels: Numerous flat, oval lenticels present. The lenticels     range in size from approximately 3 to 7 mm in width and were     approximately 1 mm in height. -   Current season shoots:     -   -   Surface texture.—Substantially glabrous. -   Internode length: Approximately 10 to 13 mm as measured in the     middle of a current season stem. -   Color of mature branches: The predominant colors are 166A and 174A     of the Greyed-Orange Group. -   Current season shoots:     -   -   Color.—Green (144A of the Yellow-Green Group) with a reddish             brown coloration on the exposed surfaces (166A of the             Greyed-Orange Group and 179A and 181A of the Greyed-Red             Group). The upper exposed surface of current season growth             exhibits a medium intensity of anthocyanins.

Leaves

-   Size: Considered moderately large for the species. Leaf measurements     have been taken from vigorous upright current season growth     approximately at mid-shoot. -   Leaf length: Approximately 150 to 182 mm. -   Leaf width: Approximately 41 to 47 mm. -   Leaf thickness: Less than 1 mm. -   Leaf form: Lanceolate and occasionally wavy and crinkled. -   Leaf tip form: Acuminate. -   Leaf upper surface color: Green varying among 137A-B of the Green     Group and 146A-B of the Yellow-Green Group. -   Leaf lower surface color: Green varying among 146A-D of the     Yellow-Green Group. -   Leaf mid-vein color: Light yellow green (150D and 154D of the     Yellow-Green Group). -   Leaf margins:     -   -   Form.—Considered crenulate.         -   Uniformity.—Considered generally uniform. -   Leaf petioles:     -   -   Size.—Considered medium.         -   Length.—Approximately 11-12 mm.         -   Thickness.—Approximately 2 mm.         -   Color.—Light yellow green (150D and 154D of the Yellow-Green             Group). -   Leaf glands:     -   -   Size.—Approximately 1 mm in height and less than 1 mm in             width.         -   Number.—Generally 3-4 per leaf.         -   Type.—Globose.         -   Color.—Brown (199A of the Grey-Brown Group). -   Leaf stipules: Early deciduous.     -   -   Size.—Length — Approximately 8-9 mm. Width — Less than 1 mm.         -   Form.—Lanceolate.         -   Color.—Light green (Yellow-Green Groups N144A-C and 151A-C),             with red (Orange-Red Group N34A, Red Groups 46A-B and             53A-B).         -   Ratio of wood (leaf) buds to flowering buds.—1 to 2 flower             buds per vegetative bud.

Flowers

-   Floral buds:     -   -   General.—The floral buds are considered to be medium to             medium large in size, conic in form, and slightly appressed             relative to the bearing shoot.         -   Color.—The bud scales are gray-brown (approximately             Greyed-Purple Group 183C-D). The buds are considered hardy             under the typical climatic conditions in the low and medium             chill zones of Texas and in central San Joaquin Valley,             Calif. climatic conditions.         -   Length and width.—Approximately 5 to 10 mm in length and 3             to 5 mm in width.         -   Blooming type.—Considered quite early in relation to other             peach cultivars commonly growing in the low to medium chill             zone of Texas. Date of full bloom was between February 1st             and February 10th during the period between 2008 and 2012             with an average full bloom date of February 5th, 12-14 days             before ‘Flordaking’ and ‘Texking’.         -   Flower type.—Showy.         -   Flower size.—Flower diameter at full bloom is approximately             32 to 40 mm. The length of the flower at the pink bud stage             before opening varied from 15 to 21 mm depending on its             stage of development.         -   Bloom quantity.—Considered abundant.         -   Flower bud frequency.—Normally 1 to 2 per node. -   Petal Size:     -   -   General.—Considered medium large for the species.         -   Width.—Approximately 14 to 15 mm.         -   Length.—Approximately 17 mm. -   Petal form: Broadly ovate. -   Petal count: Nearly always 5. -   Petal color: Light pink when young (Red-Purple Group 62D, 65C-D and     73D). -   Petal claw:     -   -   Form.—The claw is considered truncate in shape and has a             small to medium size when compared to other varieties.         -   Length.—Approximately 1 mm.         -   Width.—Approximately 1 mm or less. -   Petal margins: Generally considered smooth. -   Petal apex:     -   -   Generally.—The petal apices appear slightly domed. -   Flower pedicel:     -   -   Length.—Considered present, and having an average length of             approximately 2 to 3 mm.         -   Thickness.—Considered average, approximately 1 mm.         -   Color.—A light green (Yellow-Green Group N144D and 145A-B). -   Floral nectaries:     -   -   Color.—Bright orange (Orange Group 25A-B and N25A-C). -   Hypanthium:     -   -   Surface texture.—Generally glabrous.         -   Color.—A brownish red with light green (approximately             Yellow-Green Group 145A-B, Greyed-Red Group 178A-B, 181A and             183A-C). -   Sepals:     -   -   Surface texture.—The surface has a short, fine, and wooly             texture.         -   Size.—Average, and ovate in form. The sepals range from             approximately 5.0 to 6.7 mm in length and 3.3 to 5.0 mm in             width.         -   Color.—A brownish red with green (approximately Yellow-Green             Group 145A-B, Greyed-Red Group 178A-B, 181A and 183A-C). -   Anthers:     -   -   General.—Average in size for the species. The anthers are             approximately 1 mm in length and 0.5 mm in width.         -   Color.—Yellow (approximately Greyed-Orange Group 163B-C).         -   Pollen production.—Pollen is abundant, and is a yellow color             (approximately Yellow Groups 5A-B and 12A-13B). -   Filaments:     -   -   Size.—Variable in length, approximately 12 to 13 mm, with             the filaments slightly shorter or equal to the pistil. The             stamens are slightly below or equal with the pistil height             and do not protrude when the flowers are at the pink bud             stage of development.         -   Color.—White (approximately White Group N999D) (from R.H.S.             Colour Chart, 2005). -   Pistil:     -   -   General.—Average in size, but slightly longer or equal to             the general anther height.         -   Length.—Approximately 15 to 17 mm, including the ovary.         -   Color.—Considered a very light yellow when young             (approximately Green-Yellow Group 1C-D and Yellow Group             2C-D).         -   Pubescence.—Absent. The pistil including the ovary is not             pubescent.

Fruit

-   Maturity when described: The present variety of fruit is described,     as it would be found in its firm ripe condition at full commercial     maturity in early to mid May in the medium chill zone of Texas.     ‘Smooth Zest Two’ ripens 3-4 days after ‘Flordaking’ (not patented,     Andrews et al., 1979) and with or 1-2 days before ‘Smooth Delight     One’ (U.S. patent application Ser. No. 14/544,508) and ‘Smooth     Delight Two’ (U.S. patent application Ser. No. 14/544,522) in the     medium chill zone. -   Size:     -   -   General.—Medium large for the season and considered uniform.         -   Average cheek diameter.—Approximately 63 to 74 mm.         -   Average suture diameter.—Approximately 65 to 76 mm.         -   Average axial diameter.—Approximately 65 to 69 mm. -   Fruit form: Generally round to round-ovate in its lateral aspect.     Occasionally the fruit exhibits less symmetry when comparing the     suture height with the line opposite the suture. The fruit is     generally uniform in symmetry when viewed from the apical aspect,     but occasionally exhibits unequal halves. -   Fruit suture: Generally, the suture appears as a thin line that     extends from the base to the apex, and appears deeper at the apex,     forming a shallow basin at the apical point. No apparent callusing     or stitching exists along the suture line.     -   -   Color.—The suture normally is the same color as the             underlying blush (42A-D, 45A-D, 26A-B, 47A-B and 53A-B of             the Red Group).         -   Ventral surface.—Form — Considered uniform. -   Stem cavity:     -   -   Size.—Considered medium for the species.         -   Width.—Approximately 22 to 30 mm.         -   Length.—Approximately 25 to 30 mm.         -   Depth.—Approximately 10 to 13 mm. -   Fruit base: Generally considered truncate in form, and uniform. -   Fruit apex: Generally considered depressed and usually recessed     below the height of the apical shoulders. -   Fruit stem:     -   -   Generally.—Considered medium in length, approximately 9 to             10 mm.         -   Thickness.—Approximately 2 to 3 mm.         -   Color.—Generally a light green (144B-D and 145B of the             Yellow-Green Group). -   Fruit skin: Generally considered medium or average in thickness.     -   -   Surface texture.—The variety has no pubescence.         -   Skin acidity.—Considered neutral.         -   Tenacious to flesh.—Yes at commercial maturity.         -   Tendency to crack.—Some cracking observed.         -   Skin color.—Generally — Variable, with a small             (approximately 30%) to a large (approximately 70%)             percentage of the fruit surface covered with an attractive             blush as described below under Blush Color.         -   Pubescence.—Absent. The glabrous skin has a medium             glossiness.         -   Blush color.—This blush ranges from medium to dark red             (42A-D, 45A-D, 26A-B, 47A-B and 53A-B of the Red Group) with             many degrees of shading and blending occurring between these             colorations.         -   Skin ground color.—This is generally present in variable             percentages covering approximately 35-50% of the fruit's             surface. The skin ground color is yellow with a small amount             of green present (1B-C of the Green-Yellow Group, 2C-D, 3D,             4C-D, 5C-D and 8B-C of the Yellow Group and 14C-D of the             Yellow-Orange Group). -   Flesh color: Generally considered variable from light to medium     yellow (11C-D and 12D of the Yellow Group, 15C-D and 16B-D of the     Yellow-Orange Group and 155A-D of the White Group). -   Flesh texture: Generally, the flesh is considered firm at commercial     maturity. -   Ripening: Generally the fruit of the present variety ripens evenly. -   Flavor: Considered sweet with slightly acidic flavor. -   Aroma: Pleasant and reasonably abundant. -   Eating: Generally considered very good, particularly for an early     ripening variety.

Stone

-   Attachment: Clingstone (strongly adherent) at commercial maturity. -   Stone size: Generally considered medium-small to medium relative to     the ratio of stone to fruit size.     -   -   Length.—Approximately 27 to 29 mm.         -   Width.—Approximately 17 to 20 mm.         -   Thickness.—Approximately 14 to 16 mm. -   Stone form: Generally the stone is considered elliptical. -   Stone base angle: Considered narrow to medium. -   Apex shape: The stone apex is narrow to medium. -   Stone shape: The stone shape is generally elongated to very     elongated. -   Stone surface:     -   -   Surface texture.—Minor surface markings consists of line             grooves, numerous single pits and pit grooves.         -   Ridges.—Numerous fine ridges are present basally, and             converge towards the base of the stone.         -   Ventral edge.—Width — Considered small to medium and having             a dimension of approximately 4 to 6 mm at the mid-suture.         -   Dorsal edge.—Shape — Grooved and having moderately rough             edges.         -   Stone color.—The color of the dry stone is medium brown             (approximately 164B and 165C-D of the Greyed-Orange Group             and N199C-D of the Grey-Brown Group). The color of the             inside surface of the endocarp is primarily 164B-C and             165C-D of the Greyed-Orange Group.         -   Tendency to split.—Some splitting observed.         -   Kernel.—The kernel fills the endocarp at harvest. When dried             the shriveled kernels measure approximately 2-3 mm in             thickness, 7-8 mm in width, and 14-15 mm in length. The             colors of the shriveled kernels are variable, ranging from             medium to dark brown (164A and 165A-B of the Greyed-Orange             Group and N199C-D and 200D of the Greyed-Brown Group). -   Use: The subject variety, ‘Smooth Zest Two’, is considered to be a     nectarine tree of early-season maturity, which produces fruit which     are firm, attractively colored, and which are useful for both local     and regional fresh fruit markets. -   Keeping quality: Good. -   Resistance to insects and disease: No particular susceptibilities     were noted or claimed. -   Shipping quality: Average.

Although the new variety of nectarine tree possesses the described characteristics when grown under the ecological conditions prevailing in the low to medium chill zone of Texas, it will be understood that variations of the usual magnitude and characteristics incident to the changes in growing conditions, fertilization, pruning, and pest control are to be expected.

References

Andrews, C. P., W. B. Sherman, and P. M. Lyrene. 1979. ‘Flordaking’ peach. HortScience 14:81-82.

Anon. 2001. R.H.S. Colour Chart. The Royal Hort. Soc., London.

Brooks, R. M. and H. P. Olmo. 1997. Register of New Fruit and Nut Varieties. 3rd Edition. American Society of Horticultural Science Press, Alexandria, Va.

Byrne, D. H. and N. Anderson. 2013. TexFirst, an Early-ripening, low chill peach for the subtropics. HortScience 47(2):1803-1804. U.S. Plant Pat. No. 26,119.

Byrne, D. H and N. Anderson. Nectarine tree, Smooth Delight One. U.S. patent application Ser. No. 14/544,508.

Byrne, D. H and N. Anderson. Nectarine tree, Smooth Delight Two. U.S. patent application Ser. No. 14/544,522.

Byrne, D. H. and T. A. Bacon. 1991. ‘TexRoyal’, a medium chilling peach. HortScience 26(10):1338-1340.

Byrne, D. H. and T. A. Bacon. 2004. ‘TexKing’, an early ripening medium chill peach. HortScience 39: 442-443. U.S. Plant Pat. No. 14,627. Mar. 23, 2004.

Sherman, W. B., P. C. Andersen, and P. M. Lyrene. 1995. ‘Sunraycer’ nectarine. HortScience 30(1): 154. 

We claim:
 1. A new and distinct Prunus persica tree, substantially as illustrated and described herein. 